Power is commonly supplied to structures through electrical wires buried in the ground and protected by conduit. The conduit is first buried at a required depth using a backhoe and then wires are pulled through the conduit using a rope that has been fished through the conduit and attached to one end of the electrical wires. For smaller applications, such as in residential settings, the wires may be pulled by hand. However, in larger applications, such as in commercial settings, the wires must be pulled using a mechanical winch.
There are problems and/or dangers when using a conventional winch to pull wires through conduit. One problem is the size of the winches which must be mounted to a truck or to a trailer. In many cases, a conventional winch mounted to a truck or trailer cannot readily access the work site. An additional problem, is the need for extra workers to transport not only a backhoe, which is transported on a trailer, but also the winch, which is transported on a second truck and/or trailer. This requires two transport vehicles or multiple trips to transport the backhoe and the winch to a jobsite.
A more concerning problem with conventional winches is the damage that may be caused to the wires, conduit and/or junction boxes into which the conduit is fed. Many junction boxes, especially in commercial settings are mounted on a concrete foundation through which one or more lines of conduit pass through from the ground below. It is often difficult for an individual operating a winch to monitor the progress of the cable and electrical wires being pulled through the conduit. This is especially true when the winch must be placed a distance from the junction box due to inaccessibility. As a result, the force of the winch may pull the electrical wires too far through the conduit, thereby damaging the wires and/or conduit and, in some cases, actually pulling the junction box and concrete foundation up and off the ground.
Therefore, a need exists for a cable pulling device that is easily transportable and allows an operator more control over the tension being applied to the cable and electrical wires being pulled though a conduit.
The relevant prior art includes the following references:
Pat. No.Issue/(U.S. Patent References)InventorPublication Date5,238,225HuntAug. 24, 19935,653,293EllisAug. 5, 19975,711,636BoyerJan. 27, 19986,125,425BoyerNov. 28, 20006,553,694MartinezApr. 29, 20032009/0260265Aeschbacher et al.Oct. 22, 2009